Front panel switches - what did they do?

Charles Anthony at
Tue May 24 12:25:04 CDT 2016

On Tue, May 24, 2016 at 9:56 AM, Swift Griggs <swiftgriggs at> wrote:

> On Tue, 24 May 2016, Jon Elson wrote:
> > The early PDP-11s had a diode matrix ROM for the boot memory.  You could
> > change the boot code with a wire cutter and soldering iron.
> Is that similar to "wire wrap" ? I remember my grandmother talking about
> having to snip wires connected to diodes. I think this was in the 50's but
> it might have been the 60's, too. She mentioned something like that.
Wirewrap is solderless.

Very good for prototyping, automated wirewrapping was for some production.

-- Charles

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